package com.pet.system.util;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

public class DESOver {

	// 二十四字节	
	private final static String DES = "DES";
	static SecretKey securekey = null;
	private static String key = "wad*&_2012";
		
	private static void init(){
		byte[] kbs = key.getBytes();
		try {
			DESKeySpec dks = new DESKeySpec(kbs);
			SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);
			securekey = keyFactory.generateSecret(dks);
		} catch (Exception ex) {
			ex.printStackTrace();
		}
	}

	public static byte[] encrypt(byte[] src) throws Exception {
		if (securekey == null)
			return null;

		Cipher cipher = Cipher.getInstance(DES);
		cipher.init(Cipher.ENCRYPT_MODE, securekey);
		return cipher.doFinal(src);
	}

	
	
	public static byte[] decrypt(byte[] src) throws Exception {
		if (securekey == null)
			return null;
		Cipher cipher = Cipher.getInstance(DES);
		cipher.init(Cipher.DECRYPT_MODE, securekey);
		return cipher.doFinal(src);
	}

	
	public final static String decrypt(String data,String key) {
		init();
		
		try {
			return new String(decrypt(hex2byte(data.getBytes())));
		} catch (Exception e) {
		}
		return null;
	}
	
	public final static String encrypt(String password,String key) {
		init();
		
		try {
			return byte2hex(encrypt(password.getBytes()));
		} catch (Exception e) {
		}
		return null;
	}

	
	public static String byte2hex(byte[] b) {
		String hs = "";
		String stmp = "";
		for (int n = 0; n < b.length; n++) {
			stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
			if (stmp.length() == 1)
				hs = hs + "0" + stmp;
			else
				hs = hs + stmp;
		}
		return hs.toUpperCase();
	}

	public static byte[] hex2byte(byte[] b) {

		if ((b.length % 2) != 0)
			throw new IllegalArgumentException("IllegalArgumentException");
		byte[] b2 = new byte[b.length / 2];
		for (int n = 0; n < b.length; n += 2) {
			String item = new String(b, n, 2);
			b2[n / 2] = (byte) Integer.parseInt(item, 16);
		}
		return b2;
	}
}
